Suh Do Kwan is an offshoot of Kang Duk Won, which is itself an offshoot of Chang Moo Kwan, which was originally called YMCA Kwon Bop Bu. Suh Do Kwan was established under the name American Tae Kwon Do Association (ATKDA, not to be confused with the American Taekwondo Association, ATA) in the 1950s by Suh Young Ik when Suh emigrated to the U.S. Suh was part of wave of Korean taekwondo instructors who emigated from Korea to other countries during the 1950s and 1960s, in part as a response to the Korea Taekwondo Association (KTA) efforts to consolidate taekwondo within Korea into a single, unified style.
Suh later decided to drop the word taekwondo and simply refer to his style as Kang Duk Won style. When Suh died in 1973, his successor Don Baird renamed the style Suh Do Kwan.